[PATCH] uvc: fix cropcap v4l2-compliance failure

[Hans Verkuil <hverkuil@xs4all.nl>]

The v4l2-compliance tool expects that if VIDIOC_CROPCAP is defined, then
VIDIOC_G_SELECTION for TGT_CROP_BOUNDS/DEFAULT is also defined (or COMPOSE
in the case of an output device).

In fact, all that a driver has to do to implement cropcap is to support
those two targets since the v4l2 core will implement cropcap and fill in
the pixelaspect to 1/1 by default.

Implementing cropcap is only needed if the pixelaspect isn't square.

So implement g_selection instead of cropcap in uvc to fix the v4l2-compliance
failure.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
---
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
index 43e953f..7078d3e 100644
--- a/drivers/media/usb/uvc/uvc_v4l2.c
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -1018,26 +1018,35 @@ static int uvc_ioctl_querymenu(struct file *file, void *fh,
 	return uvc_query_v4l2_menu(chain, qm);
 }
 
-static int uvc_ioctl_cropcap(struct file *file, void *fh,
-			     struct v4l2_cropcap *ccap)
+static int uvc_ioctl_g_selection(struct file *file, void *fh,
+				 struct v4l2_selection *sel)
 {
 	struct uvc_fh *handle = fh;
 	struct uvc_streaming *stream = handle->stream;
 
-	if (ccap->type != stream->type)
+	if (sel->type != stream->type)
 		return -EINVAL;
 
-	ccap->bounds.left = 0;
-	ccap->bounds.top = 0;
+	switch (sel->target) {
+	case V4L2_SEL_TGT_CROP_DEFAULT:
+	case V4L2_SEL_TGT_CROP_BOUNDS:
+		if (stream->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+			return -EINVAL;
+		break;
+	case V4L2_SEL_TGT_COMPOSE_DEFAULT:
+	case V4L2_SEL_TGT_COMPOSE_BOUNDS:
+		if (stream->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+	sel->r.left = 0;
+	sel->r.top = 0;
 	mutex_lock(&stream->mutex);
-	ccap->bounds.width = stream->cur_frame->wWidth;
-	ccap->bounds.height = stream->cur_frame->wHeight;
+	sel->r.width = stream->cur_frame->wWidth;
+	sel->r.height = stream->cur_frame->wHeight;
 	mutex_unlock(&stream->mutex);
-
-	ccap->defrect = ccap->bounds;
-
-	ccap->pixelaspect.numerator = 1;
-	ccap->pixelaspect.denominator = 1;
 	return 0;
 }
 
@@ -1449,7 +1458,7 @@ const struct v4l2_ioctl_ops uvc_ioctl_ops = {
 	.vidioc_s_ext_ctrls = uvc_ioctl_s_ext_ctrls,
 	.vidioc_try_ext_ctrls = uvc_ioctl_try_ext_ctrls,
 	.vidioc_querymenu = uvc_ioctl_querymenu,
-	.vidioc_cropcap = uvc_ioctl_cropcap,
+	.vidioc_g_selection = uvc_ioctl_g_selection,
 	.vidioc_g_parm = uvc_ioctl_g_parm,
 	.vidioc_s_parm = uvc_ioctl_s_parm,
 	.vidioc_enum_framesizes = uvc_ioctl_enum_framesizes,